The chemokine receptor CCR2 is a G protein-coupled receptor that is involved in many diseases characterized by chronic inflammation, and therefore a large variety of CCR2 small molecule antagonists has been developed. CCR2-RA-[R] displaces [
125
I]CCL2 from CCR2 with an pIC
50
value of 6.1. The pK
D
of CCR2-RA-[R] for CCR2 and CCR5 is 8.8±0.1 and 7.0±0.1, respectively. CCR2-RA-[R] inhibits CCR2 non-competitively by blocking activation-associated conformational changes and formation of the G protein-binding interface. The binding pocket of CCR2-RA-[R] is highly enclosed and possesses a balanced combination of hydrophobic and polar features, all of which favors pocket “druggability”.